Explosives are those substance which provides extreme heat and energy and a sharp cracking sound on combustion. They usually have less potential energy than fuels, but their high rate of energy produces a great blast pressure.For a chemical to be an explosive, it must exhibit all of the following: Rapid expansion (i.e., rapid production of gases or rapid heating of surroundings);evolution of heat;rapidity of reaction; and initiation of reaction.
Important Chemical Explosives
RDX (Research & Development Explosive): RDX was firstly invented by a German chemist Haning in 1899 in the form of pure white crystallined powder. The chemical name of RDX is cyclo trimytheline trinitramine and sometimes it is also called plastic exploder and this explosion in USA is called cychlonite, in Germany it is called Hexogen and in Italy it is called T -4. If plastic substance like poly butinc acrylic acid be mixed in RDX in small amount then Plastic Bonded Explosive (PBE) is obtained. Another form of explosive is C-4 which is a deadly destructor or cracker and to achieve an optimal level of requirement some powder of aluminium is mixed. Plastic Bonded Explosive (PBE) is today frequently utilised by the terorists and fundamentalist group. The explosion energy in normal RDX is nearly 1510 kcal.
TNG (Tri Nitro Glycerine): It is a colourless oily liquid which is utilised in making dynamite. TNG is also called Nobel's oil. This explosive was invented in 1846. It is prepared by mixing conc. H2S04 and cone. HNO3 with Glycerine.
TNT (Tri Nitro Toluene): This is the most frequently used explosive and it is prepared by the reaction of toluene (C6H5 - CH3) and conc. H2S04 and conc. HN03. This explosive was firstly invented in 1863 while its commercial used was started in 1914 and the first user of TNT was UK troops.
Dynamite: This is also an explosive which was invented by Nobel Alfred in 1863. This is prepared by absorbing inert substances like powder of wood or absorbing in Kieselguhr. At present in making dynamite on the behalf of nitro glycerine sodium nitrate is used. In xelatine dynamite a very small amount of nitro cellulose is mixed up.
TNP (Tri Nitro Phenol): This is also known as picric acid and TNP is prepared by the reaction of phenol with cone. H2SO4 and cone. HNO3. TNP is also an ultra exploder explosive.